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Dendrology question

I have heard of the large quantity of water to pass through tree on hot day. Would one expect this to pull significant heat out of Apis nest in hollow ? Mostly from sides, greenwood ?
Cheers,
Drew
p.s Seems fair enough to me, but alas, as with thermodynamics, I am frustrated by ignorance

Re: Dendrology question

The water passes through vessels (hardwoods) or trachaeids (softwoods) that occur in the living part of the tree. These are structurally isolated from the living/dead tissues that form the walls of the cavity. Cooling would only take place at the surface of the leaves or needles where the water changes phase from liquid to vapor as it is transpired from the tree. The result - no heat lost to the combs.

Re: Dendrology question

Originally Posted by pkalisz

Cooling would only take place at the surface of the leaves or needles where the water changes phase from liquid to vapor

Not totally the case. The conversion from water to vapor may be the point of greatest cooling, but travelling from the cooler underground to those leaves it will also absorb heat from the surrounding tissue. To my thinking...not enough to substantially cool the bee nest but it will remove some of the heat.
All you have to do to test this is to fill a bathtub with cold water and jump in. The water will chill you quickly....even without any significant evaporation.

Dan www.boogerhillbee.com
Experience is a hard teacher because she gives the test first, the lesson afterwards

Re: Dendrology question

I wouldn't dismiss it outright. There is a heck of a lot of water on a good size tree moving up on a hot day. That water is being drawn at soil temp, which is a fair bit cooler than air in summer midday.

But I think the wood itself wood insulate against any significant heat exchange at that small temperature differential. Maybe in a full sun situation it would reduce solar gain from the exterior, but I just don't see it pulling heat from the interior.

Re: Dendrology question

My understanding to is that there is a heck of a lot? of water movin and its got to be @ least cool? coming up, this would make for a nest in a cool water jacket ? Like they plug the athletes into Be very curious to know, if the hive is 95, I would think the water going by although insulated, could be a big help. Perhaps the water pushes right up against the back side of that prop. all around ? I've got a dissected poplar trunk/nest, looking @ cross section it seems possible, but I'm no dendrologist

Re: Dendrology question

It will cool the nest to a very small degree. Ventilation will cool it to a much larger degree. The bees can generate so much heat in the winter to keep warm that this little heat loss in the summer is insignificant or mildly appreciated.